1. Field of the Invention
The present invention relates to an inkjet recording apparatus, and more particularly, to the structure of an inkjet recording apparatus which achieves a reduction in size of the whole apparatus.
2. Description of the Related Art
In recent years, inkjet recording apparatuses (inkjet printers) have become widely used as recording apparatuses which print and record images that have been captured by a digital still camera, and the like. The inkjet recording apparatus has a plurality of nozzles in a head, and records a prescribed image on the recording medium by ejecting ink droplets onto the recording medium from the nozzles. In many cases, inkjet recording apparatuses are situated on the same desk as other equipment, such as a personal computer, a scanner, a digital camera, and the like, and there are cases where these items of equipment are disposed in a stacked fashion in order that a plurality of items can be arranged compactly on one desk. Therefore, it has been sought in the inkjet recording apparatus to reduce the installation space by reducing the overall size of apparatuses and making them thinner in shape, as well as seeking to improve operability and maintenance characteristics by using a common surface of the apparatus for operations such as switching the power on and off, and maintenance tasks, such as supplying paper or replacing the ink.
Japanese Patent Application Publication No. 2004-338383 discloses that the overall size of an inkjet recording apparatus is made more compact by simplifying the structure of an ink supply system inside the apparatus, by adopting a method for supplying ink by connecting an ink cartridge to the recording head only when necessary. However, it is stated that ink is introduced into the inkjet head from an ink accommodating vessel due to the negative pressure of a pump connected to the inkjet head, but there is no disclosure regarding the method of generating a negative pressure inside the inkjet head during printing. Furthermore, it is necessary to provide a pump which connects to the inkjet head, and this is disadvantageous in terms of the compactification of the inkjet recording apparatus.
Japanese Patent Application Publication No. 2001-63091 discloses an ink supply system in which a negative pressure generating vessel which generates negative pressure due to a restorative force when it is deformed elastically is provided between the inkjet head and the ink tank. However, there is no concrete disclosure regarding the structure or control method employed to control the internal pressure of the inkjet head when the negative pressure generating vessel and the ink tank are separated, in a mode where the negative pressure generating vessel (of the inkjet head) and the ink tank are only connected together when necessary.